100B-29 |
Application of composite films of wheat gluten and gelatin to guavas |
C. R. F. Grosso, P. S. TANADA-PALMU, and F. M. Fakhouri. Faculty of Food Engineering/Department of Food Planning and Nutrition, State University of Campinas (UNICAMP), Cidade Universitária Zeferino Vaz, Campinas - SP, 13083-970, Brazil In Brazil, the greater part of agricultural products are lost during storage, so prolonged storage life is a challenge. Composite films of wheat gluten and gelatin were applied to guavas in order to reduce losses of weight and firmness during storage. Edible films can provide an alternative for extending the post-harvest storage of fruits and vegetables. Guava is a typical fruit in tropical areas of the world, widely produced and consumed in Brasil. To study the ability of composite films of wheat gluten and gelatin to extend shelf life of refrigerated guavas and evaluate the influence of different types and mixtures of films on the quality attributes of guavas, such as weight loss and firmness. Single and composite films of wheat gluten and gelatin were applied to coat fresh guavas. Guavas were dipped in a film-forming solution of gelatin, gluten and a mixture of the two (4 gelatin:1 gluten). They were stored in a refrigerator for 2 weeks and during this period, the weight loss was registered and the firmness measured with a texture analyzer. The gelatin film reduced losses of weight and firmness (7.83% and 7.97 N, respectively) of the guavas in this study, compared to uncoated fruits (8.31% and 6.01 N). The guavas coated with the composite film of gluten and gelatin showed similar weight and firmness losses (8.56% and 5.77 N) to the uncoated fruits, and the guavas with gluten film showed higher losses (9.99% and 3.99 N). This behavior is in accordance with the water vapor permeability results tested with the films, since the gelatin film had the lowest value and the gluten film, the highest. The gelatin film extended the guava shelf life, reducing their weight and firmness losses throughout storage compared to uncoated guavas. The composite film of gluten and gelatin, did not.
Session 100B, Food Packaging
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